Distributor 1941 3 Bolt Design
 

Looking for some help finding a rebuilding document for the distributor. About 10 years ago I had one but can't seem to locate it. THe issue I have is the car will run for approx. 15mins and then start missing at high rpm and then continues to degrade over the next 5 mins. to the point it will no run at all untlil it cools off. I'VE BEN CHASING THE ISSUE AS IF IT WAS A COIL ISSUE and or power to the coil but today I discovered that one of the points must be sticking as the engine heats up. THis really presented itself as a typical early ford coil performance issue. Anyways if anyone can share a link to rebuilding this I would appreciate it. Enjoy the long wkend.!!!!

Re: Distributor 1941 3 Bolt Design
 

I would take a look at replacing the condenser.

Re: Distributor 1941 3 Bolt Design
 

This was the identical problem I had with my '35 apparently caused by a not so high quality set of points. Over time the points would become tight on the pivot post, and start sticking which lead to burning at the point contacts. I first thought it was the coil and/or condenser and replaced these components with known good backup parts, but finally found the real culprit when I broke down on the side of the road just west of Lincoln, Nebraska during a cross country tour. The points were not pivoting properly on their mounting posts, plus the flat springs on the contact points were much weaker than some nos point sets that I have. After correcting this problem on the side of the road in June of '13, I have put 10-15k miles on this same car with zero distributor problems in the last two years. When you get these old helmet distributors set up correctly, they will work well for a good long time!

Re: Distributor 1941 3 Bolt Design
 

The condenser serves two purposes. One, it builds a high intensity charge so that it will aid in reversal of the electrical flux in the core of the coil very rapidly and keep the circuit breaker points from arcing a spark as they open. Secondly, it creates a longer coil secondary output due to its holding the charge on the primary a millisecond more after the breaker points open. If it isn't charging up or it's leaking the built up charge through the dielectric as fast as it is charging, the ignition will suffer dramatically from burning of the points and/or poor secondary high tension output.

The condenser is the weakest link in the system and also the most vulnerable if poorly made. It would be a good idea to check the points and make certain that they are serviceable or just replace and re-gap them. If they are bad, the finger will be on the condenser too so find a good one of those. Our resident ignition specialist, Bubba, has some good recommendations about points & condensers on some of the ignition related threads here on the barn. He does this stuff for a living.

If a person changes the breaker & condenser parts and it still has temperature related problems, the coil would be the next item to have tested or replace/overhaul.

Re: Distributor 1941 3 Bolt Design
 

I have the dist. apart and one of the two points was not quite as free on the pivot post however it was hardly noticeable . What I did discover is on the one set the gap was tight and the points had developed a burnt high point. I will hit NAPA tomorrow to replace both sets (already replaced the Condenser) and see how it does I'm confident this is likely the issue believe as the Distributor heated up from general engine heat it was just enough expansion of the metal parts to close the gap on this one set of points. I find this very interesting as all of my focus has been on the Coil (s) or other electrical issues never considered one set of the points being screwed up. The issue presented itself exactly like everyone talks about issues with the Ford distributor coils.
Hopefully this saga will be over tomorrow and will let everyone know when the story is over.

Re: Distributor 1941 3 Bolt Design
 

Saga is not over!! Have had this dist out approx. 8 or 9 times in the last week. I know there is a short to ground when the failure occurres. the only part I have not changed is the small insulator that sits below the brass cup which feeds power down to the points. I also know someone dealing with this exact issue and has even converted to solid state points in an attempt to resolve it without any luck. I'm not all reluctant to sending the dist to Skip in Fl. I'm just don't think a typical rebuild will fix this issue. At this point I think I need to find another distributor rebuild it and at least be sure this issue is gone. At this point shoot me . One other note I'm running the conversion plate with an external Coil. Any thoughts

Re: Distributor 1941 3 Bolt Design
 

There is another thing that may be the problem. The rotor arm can start to fail and thye spark will jump through and ground out on the distributor shaft. Look closely at the shaft with a magnifying glass and look for blackening where the spark has been coming through. This has been mentioned before, and the advice was to fit a new rotor and try to help things by applying heatshrink tubing to the shaft in the critical area.

I had a helmet distributor and it failed in the way you describe. Drives ok. Deteriorates. Stops. Let it cool down, carry on until it degrades again.

I have rebuilt it with new parts but have not tested it yet.

You can also help by making sure you do not have resistive leads or plug caps, and keeping the plug gap down to .025"

Mart.

Re: Distributor 1941 3 Bolt Design
 

Matt

I tried a different rotor (not new but)... I think the key point is if I take an ohm meter with the power feed disconnected coming from the external I get conductivity (like the points are closed when I turn the engine. Its not until the engine cools down that I can see the point opening and closing I really believe I have a short when the engine heats up just can't put my figure on it. I'm going to find someone with a distributor I can try just to prove I'm not crazy.

Re: Distributor 1941 3 Bolt Design
 

ok tried it again no dice I'm beginning to question weather these NAPA points should be set the same as factory. I did look real close at the shaft and I also coated it with 3M liquid tape in the center however I have fairly convinced myseld that it has something to do with the points. Stay tuned once I find the solution I will let you guys know

Re: Distributor 1941 3 Bolt Design
 

The points are just circuit breakers timed to get proper spark to the plugs and build a good charge between openings. You can use a volt ohm meter to test whether they are properly isolated and breaking/closing the circuit as they should.

Make certain your distributor drive is in good condition and properly engaged with the slot. There are instructions on several threads on the barn about timing the distributor. The operator's manual printed by FoMoCo for you vehicle gives a good instruction on setting up the distributor. Contact Bubba if you need professional help. He can test the stuff and insure function for you.

Re: Distributor 1941 3 Bolt Design
 

I've read all the replys and didn't see where you changed the condenser. Or did I miss it. Walt

Re: Distributor 1941 3 Bolt Design
 

Condenser

Re: Distributor 1941 3 Bolt Design
 

Veeder,

There are a few things you have not told us.

1. Are you running 6V or 12V?

2. Is there a resistor in the system? What is its value?

3. You are using a modern, tube coil with a conversion kit. What coil and what is the resistance of the coil?

4. How many volts are you putting to the distributor ... cold? Hot?

I'd kinda want to make sure the system feeding the distributor is on spec and not the root cause of the problem.

Re: Distributor 1941 3 Bolt Design
 

Are you talking about the helmet style distributor? I have the same issues with mine. It had been converted to 12v. Just got the car so I haven't been able to check everything out. But I contacted Bubba the distributor guy and for $300 he can convert it to electronic ignition. Not sure what unit he uses, I am guessing Pertronix. But that might be an option for you if you don't mind losing the condensor and the coil attached to the top of the distributor.

Re: Distributor 1941 3 Bolt Design
 

Hoop

good questions

1) using a 6 volt system
2) There is the stock resistor in the system which is mounted under the dash next to the ckt breaker
3) Using the conversion kit with the external coil have tried three different coils
4)I don't have the resistance of the coil hot but cold they are
+ to - no wires attached approx. 3 ohms
high voltage output to + or - approx. 7.5k ohms
the voltage is approx. 3 volts going to the coil not measured today but I believe that's what I had.


41 Joe
I'm still leaning towards fixing this thing not converting it when it is hot the points don't appear to be opening until the dist cools down. I have to check the wires and the caps to be sure there is no rust inside I've checked one side and it is perfect. I really don't think it is the issue but will check.

Bob

Re: Distributor 1941 3 Bolt Design
 

Appreciate all the feedback have ordered parts today decided to
replace coil
rotor
the plate that the points mount to (I'm still convinced there is a short when it heats up)
points (ordered the points with the brass sleeve)
end caps
going to pull the plugs just to check them out

will let you guys know how it turns out

Re: Distributor 1941 3 Bolt Design
 

I'm with hoop, sure you need a 1-1.5 ohm coil with the resister under the dash. If this is so, surely you can bypass the resister under the dash, keep the coil that's already on there and test drive it.
This will tell you if it's the coil that's wrong, which I think it is, same as hoop. No parts to buy yet, can be done with a test lead with crocodile clips.
Quick and easy.
Martin.

Re: Distributor 1941 3 Bolt Design
 

Only read hoops reply before, didn't see you got a bunch of parts to replace, what coil did you get?
Martin.

Re: Distributor 1941 3 Bolt Design
 

As a side note related to the resistor under the dash. About 5 years ago I discovered that the car started so much faster with the ignition resistor bypassed. What I have done is installed a relay tied to the starter switch and only when the engine is craking the ignition resistor is bypassed. wORKS NICELY. However recently with these issue I have disconnected the relay and only bypass the resistor if I have to keep the car running and get it home helps sometimes TO be honest at this point the coil or cap could be root cause but I'm not convinced. I'll take pics of things that I find as this progresses so maybe I learn something and can share

Re: Distributor 1941 3 Bolt Design
 

Veeder, I have been traveling and have not been keeping up on this thread. After just reading this last post I remembered a problem that I once had with an under the dash wire wound resistor. It worked fine when wire was cold, but as it heated up, it's resistance became very high due to a poor crimp connection(s) at ends of resistor wire. After fixing these wire crimped connections with high temp solder....no more problem. May be worth checking this out. Just a thought.

Edit: Another thought....There is a very simple diode wiring circuit that could replace the relay you memtioned. It will only conduct when starter is energized to temporarily give full voltage to to the coil for startup, then this drops out of the circuit, and you go back to the normal voltage to the coil supplied through the resistor, assuming your resistor is ok. Send me a pm if you would like a circuit diagram on this.